A problem often encountered when dispensing liquid from a container is that spillage of the liquid occurs. For example, pouring gasoline from a hand held container into a fuel tank mounted on a lawn mower might result in gasoline being spilled onto a hot engine causing the gas to ignite and harming an operator. This situation is not only more likely, but also particularly dangerous when the container is filled to maximum capacity.
A similar scenario exists when filling windshield washer reservoirs with cleaning fluid, the primary differences being the working area in the engine compartment is tightly constrained exacerbating the problem, and any spillage may not immediately endanger a user. However, lingering environmental effects may be incurred.
Multiple piece assemblies using intermating conical or domed structures are known forming a rotatable valve where openings in each piece are rotatably aligned to allow dispensing of fluids. This design requires a user to first rotate the valve in order to open it, reposition one's hands and then tip the container to dispense the liquid. This process encourages spillage as indicated supra.
Older designs for valve mechanisms used on gasoline containers include pivoting flapper type valves. These types of valves are made of metal, require complex hinge and actuation apparatus, and are generally unsuitable for low cost plastic injection molding manufacturing techniques.
Metal plunger type valves have been used on gasoline containers. However, these valves also require complex hinge and actuation apparatus, and are generally unsuitable for very low cost plastic injection molding manufacturing techniques used in high volume production.
Some manufacturers have placed a rotatable valve directly in line with a spout such as FloTool'S™ Spill Saver Oil Spout.
Another type of gasoline container is the Smart Fill Fuel Can® made by Briggs and Stratton where a nozzle must be rotated, the container inverted and the nozzle placed into the mouth of a gas tank. With the mouth of the gas tank supporting the full weight of the gas and container, the container is pushed downward to cause the gas to flow into the tank. This design is still complex, and expensive to produce using known plastic manufacturing techniques, including assembly of the various components. Further, pushing downward with a full gas container onto a plastic fuel tank weakly mounted on a hot lawn mower, could create a potentially hazardous situation.